1. Field of Invention
This invention relates to apparatus for studying the relation between acoustic signals and hydraulic pressure variations in water and fish behavior. More specifically, it relates to apparatus simulating a specific fish and its perception of acoustic signals and hydraulic pressure variations for correlation with fish movement towards, or away from, zones of danger to fish, such as the intakes of hydroelectric power generating turbines.
2. Prior Art
Studies in the past of fish behavior was based on the assumption that the sound field factors influencing fish movement could be represented by mathematical models based on the acoustic fields of simple sources such as dipoles and monopoles. These studies generally deal with the compressional wave component of sound fields and neglect the particle motion component. They do not adequately describe the sound fields that influence fish behavior, expecially in areas of high turbulence. The lateral line of fish is known to be a very important sensory organ, containing hair cells which transfer mechanical hair motion caused by pressure differences and particle motion to neuro-electrical impulses. The function of this important sensory organ is not taken into account by methods known to the art.